It's been about a year since I last changed the oil, and I've put about 10k miles on this change. I used Mobile1 5w30 full syn and a good filter.

I'm thinking about doing an oil change using a syn. blend this time around, and doing a Seafoam treatment (oil, gas & vac lines) to clean up some of the mess I've made by waiting so long to change the oil. Since I'm having the timing belt changed in a few weeks I'll change the oil again with Mobile1 full syn and then change it every 3-5k like it should be.

Is it ok to use a syn blend for a few weeks and then go back to full syn?

Any other things I can do to "clean up" my dirty oil lines?

 

no it isnt. full synthetic. all the time. always. why would you even want to do that? theres no possible reason to put semi-synth in there.

although i change my oil every 5k with mobil1, 10k probably didnt hurt anything, this oil is pretty good. unless you turn your car off when the turbo is still glowing red. seafoam it, change the oil, and your good. you dont have to change your oil to do a timing belt.

 

you don't want to run your oil for 10k miles for a year. i usually change my oil every 3.5k. oil change kit for me is only 35 bux using ful synth mobil 1 and a mobil 1 filter. i only go through about 3 or 4 oil changes a year so it's not a big deal for me. i wouldn't let any cars oil go past 5k even if it's oil like mobil 1. you can add seafoam in your crankcase to clean your lines but with your oil as dirty as it is, i don't think it'll clean much. also use .5 bottle of seafoam in your gas tank to help keep the filter and injectors clean.

 

Thanks for the replies. The reason for using synthetic blend oil for my next change was to save a few bucks since it will only be used for a few weeks max. The thinking was, change the oil now, and flush the system clean with syn. blend and Seafoam, and then change the oil again with full synthetic when I do the timing belt since it's being worked on anyways. I'll just use full synthetic when i do my oil change. Thanks for the advice.

Any recommendations on oil? With 130k miles on the clock, does it help to use the Mobil1 high mileage oil? Or do most of you stick with the standard synthetics?
2001 Audi A4 1.8TQM

 

i have 120k on the clock and i've tried 10w40(high mileage, advanced protection and all that stuff) and 5w30 and honestly, i don't notice much of a difference. you should do the oil change first and then wait to do the timing belt. i wouldn't run any longer on that oil.

 

Um... Change your oil more often than that. Thats crazy. It would be one thing if you had a 2.8, but you have an oil abusing 1.8t. In addition to that, you have high-ish mileage. Is a $30 oil change every 3.5-4k miles really that much of an inconvenience? Even every 5k is acceptable... 10k? No. Bad boy.

 

I'd change it every 2500-3K miles. Stay away from those synthetic blend bull crap. The only true synthetic oils are royal purple, ams oil, and joe gibbs.

 

i don't drive that much, so i change my oil twice a year. i definitely use full synthetic though.. i would not suggest skimping out on something so critical as oil!